The invention relates generally to firearms, and more particularly, to a revolver comprising: (1) a cylinder that rotates a distance about its longitudinal axis in response to a shot, and (2) an impact base that supports the bullets in the cylinder from behind.
As used herein, xe2x80x9crevolverxe2x80x9d refers to a firearm having a cylinder that rotates to align a cartridge with the barrel for firing. The term xe2x80x9crevolverxe2x80x9d includes pistols and rifles that include such a cylinder.
During rotation of the cylinder of prior art firearms, the bullet bases of the bullet shells glide along the impact base. For this reason, the impact base must be smooth, clean, and free of obstructions. The weapon becomes unusable if the material from a breaking ignition capsule penetrates into the bore of the striking pin. Such cases, however, are very rare. The penetration of sand into the weapon is more common. If a small grain of sand becomes lodged between the impact base (sometimes referred to as a recoil plate) and the bullet base when a shot is fired, it presses into the materials and obstructs the rotation of the cylinder. In this case, the marksman""s hand must grip the cylinder and support its rotation.
If the weapon is a big game rifle, the reliability with which a second shot is made is of vital importance. The same applies to a weapon used for purposes of defense.
In modem cylinder revolvers, the cylinder usually swings out to the side. This is disadvantageous because, when the cylinder swings out, the empty bullet shells must glide along the impact base, which, in the case of a damaged impact base, sand in the weapon, or problems such as a torn capsule of the type described above, causes problems.
To avoid such problems, one can provide that, when the weapon is opened, the cylinder lifts itself away from the impact base in its first movement, as is, for example, the case with a drop barrel revolver, or in antique revolvers, in which the cylinder moved axially away from the impact base.
Problems of the type mentioned above rarely occur in revolver bullets, which are relatively weak. For this reason, and for reasons of cost and weight, revolvers are now usually made with rigid frames in which the cylinder remains in place (the bullet shells are ejected individually and chamber by chamber) or in which the cylinder can swing out to the side.
By contrast, the bullet shell of a powerful bullet undergoes considerable plastic deformation in the bullet case. The bullet shell deforms to such an extent that it is pressed against the walls of the bullet case. The fired bullet shell is then considerably pre-stressed when it comes to rest against the impact base. If this occurs in a revolver weapon, the elongated bullet shells can significantly impede the rotation of the cylinder. The problems described initially are, thus, intensified in this context.
A revolver is known in which the problems described above do not occur or are substantially diminished (i.e., Russian military revolver, Nagant model). To provide a seal against gas, a block forming the impact base pushes against the cylinder immediately following each shot and presses the cylinder forward. Before the cylinder can rotate further after the shot, the block is removed, thus permitting unobstructed rotation of the cylinder, as it is only the force of a spring that presses it against a rear cover plate. However, this design is complicated and not as well suited for high bullet power.
Otherwise, the impact base along which the fired bullet shells scrape is simply finely planed or polished. This is usually sufficient for small firearm bullets unless, for example, sand becomes lodged between the impact base and the bullet base. However, in a revolver gun that fires a modem high-powered hunting bullet, even larger-grained dust particles becoming lodged between the bullet base and the impact base is sufficient to impede or even prevent the rotation of the cylinder.